diff --git a/lock.c b/lock.c
index 29bebb15..3c55a68c 100644
--- a/lock.c
+++ b/lock.c
@@ -245,6 +245,47 @@ pid_t uwsgi_lock_fast_check(struct uwsgi_lock_item *uli) {
 
 pid_t uwsgi_rwlock_fast_check(struct uwsgi_lock_item *uli) { return uwsgi_lock_fast_check(uli); }
 
+#elif defined(UWSGI_LOCK_USE_POSIX_SEM)
+
+#define UWSGI_LOCK_SIZE         sizeof(sem_t)
+#define UWSGI_RWLOCK_SIZE       sizeof(sem_t)
+#define UWSGI_LOCK_ENGINE_NAME  "POSIX semaphores"
+
+#include <semaphore.h>
+
+struct uwsgi_lock_item *uwsgi_lock_fast_init(char *id) {
+        struct uwsgi_lock_item *uli = uwsgi_register_lock(id, 0);
+        sem_init((sem_t*) uli->lock_ptr, 1, 1);
+	uli->can_deadlock = 1;
+        return uli;
+}
+
+struct uwsgi_lock_item *uwsgi_rwlock_fast_init(char *id) { return uwsgi_lock_fast_init(id) ;}
+
+void uwsgi_lock_fast(struct uwsgi_lock_item *uli) {
+        sem_wait((sem_t *) uli->lock_ptr);
+        uli->pid = uwsgi.mypid;
+}
+
+void uwsgi_unlock_fast(struct uwsgi_lock_item *uli) {
+        sem_post((sem_t*) uli->lock_ptr);
+        uli->pid = 0;
+}
+
+pid_t uwsgi_lock_fast_check(struct uwsgi_lock_item *uli) {
+	if (sem_trywait((sem_t *) uli->lock_ptr) == 0) {
+		sem_post((sem_t*) uli->lock_ptr);
+                return 0;
+        }
+        return uli->pid;
+}
+
+pid_t uwsgi_rwlock_fast_check(struct uwsgi_lock_item *uli) { return uwsgi_lock_fast_check(uli); }
+void uwsgi_rlock_fast(struct uwsgi_lock_item *uli) { uwsgi_lock_fast(uli);}
+void uwsgi_wlock_fast(struct uwsgi_lock_item *uli) { uwsgi_lock_fast(uli);}
+void uwsgi_rwunlock_fast(struct uwsgi_lock_item *uli) { uwsgi_unlock_fast(uli); }
+
+
 #elif defined(UWSGI_LOCK_USE_OSX_SPINLOCK)
 
 #define UWSGI_LOCK_ENGINE_NAME "OSX spinlocks"
diff --git a/uwsgiconfig.py b/uwsgiconfig.py
index 54d7cc00..3954b1b0 100644
--- a/uwsgiconfig.py
+++ b/uwsgiconfig.py
@@ -415,16 +415,22 @@ class uConf(object):
             if uwsgi_os == 'Linux' or uwsgi_os == 'SunOS':
                 locking_mode = 'pthread_mutex'
             # FreeBSD umtx is still not ready for process shared locking
-            #elif uwsgi_os == 'FreeBSD':
-            #    locking_mode = 'umtx'
+            # starting from FreeBSD 9 posix semaphores can be shared between processes
+            elif uwsgi_os == 'FreeBSD':
+                 try:
+                     fbsd_major = int(uwsgi_os_k.split('.')[0])
+                     if fbsd_major >= 9:
+                         locking_mode = 'posix_sem'
+                 except:
+                     pass
             elif uwsgi_os == 'Darwin':
                 locking_mode = 'osx_spinlock'
 
         if locking_mode == 'pthread_mutex':
             self.cflags.append('-DUWSGI_LOCK_USE_MUTEX')
         # FreeBSD umtx is still not ready for process shared locking
-        #elif locking_mode == 'umtx':
-        #    self.cflags.append('-DUWSGI_LOCK_USE_UMTX')
+        elif locking_mode == 'posix_sem':
+            self.cflags.append('-DUWSGI_LOCK_USE_POSIX_SEM')
         elif locking_mode == 'osx_spinlock':
             self.cflags.append('-DUWSGI_LOCK_USE_OSX_SPINLOCK')